Consumer electronics requirements demand more integrated circuits in an integrated circuit package while paradoxically providing less physical space in the system for the increased integrated circuits content. Continuous cost reduction is another requirement. Some technologies primarily focus on integrating more functions into each integrated circuit. Other technologies focus on stacking these integrated circuits into a single package. While these approaches provide more functions within an integrated circuit, they do not fully address the requirements for lower height, smaller space, and cost reduction.
One proven way to reduce cost is to use mature package technologies with existing manufacturing methods and equipments. Paradoxically, the reuse of existing manufacturing processes does not typically result in the reduction of package dimensions. Still the demand continues for lower cost, smaller size and more functionality. The response in the assembly and packaging area are more advanced packages such as ball grid array (BGA), chip scale package (CSP), direct chip attach or wafer-level CSP.
Different fine-pitch BGA (FBGA) designs are already on the market and gaining widespread acceptance. These near-CSPs typically achieve die size plus 1.5 mm. Larger packages would therefore qualify for the CSP definition (package size=max. 1.2 times die size) while smaller packages would not. Developments continue to try to realize a die size plus 1.0 mm package.
The FBGA has been well accepted in the market because it uses standard process technology and package construction and is lower cost when compared with standard plastic BGA packages available today in the market. Even though the FBGA package uses standard process technology, it is still struggles to achieve low cost stacking of integrated circuits.
Thus, a need still remains for a stacked integrated circuit package-in-package system providing low cost manufacturing as well as reduce the integrated circuit package height. In view of the ever-increasing need to save costs and improve efficiencies, it is more and more critical that answers be found to these problems.
Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.